Door check and hold-open



Feb. 2, 1965 T. A. SCHAAD 3,

DOOR CHECK AND HOLD-OPEN 2 Sheets-Sheet 1 Filed Jan. 22, 1962 INVENTOR.

/{gaudy ATTORNEY Feb. 2, 1965 T. A. SCHAAD 3,167,807

DOOR CHECK AND HOLD-OPEN 2 SheetsS'neet 2 Filed Jan. 22, 1962 INVENTOR ATTORNEY .Zfmam 4. 62/5004 United States Patent ration of Delaware Filed Jan. 22, 1962, Ser. No. 167,652

6 Claims. (Cl. 16-85) I This invention relates generally to door operating mechanisms, more particularly to a door check and holdopen device; and with regard to certain of its more specific aspects, to a device of the type indicated particularly adapted to maintain a door pivoted about a horizontal axis in a vertical closed and intermediate opened positions and to support both the door and articles placed thereon in a horizontal full opened position.

The invention contemplates a relatively simple and compact door check and hold-open device and is herein illustrated and described as applied to a counter-type refrigerator, freezer or similar cabinet having a horizontally hinged door which is normally used in a horizontal opened position to support various items prior to or upon their removal from the cabinet. The illustrative embodiment of the invention features a bell crank mounted detent roller which is biased by a clock-type spiral spring to positively engage a detented sector formed on a pivotally mounted end of one link of a folding linkage extensibly interconnecting the door and cabinet. The clock type spring is torsionally interposed betwen the bell crank and the pivotal mounting of the sector link and progressively increases the door supporting, hold-open maintaining force acting on the detent engaging roller.

The foregoing and other objects, advantages, and features of the invention will be apparent from the following description of the preferred illustrative embodiment, having reference to the accompanying drawings in which:

FIGURE 1 is a side elevational view of a counter-type refrigerator with portions thereof broken away to show the door check and hold-open device of the invention in its door closed position and in several door opened positions in broken line phantom;

FIGURE 2 is an enlarged fragmentary sectional view taken in the direction of the arrows and substantially in the plane of the line indicated at 22 of FIGURE 1;

FIGURE 3 is an enlarged sectional view taken in the direction of the arrows and substantially of the plane of the line indicated at 3-3 of FIGURE 1; and

FIGURE 4 is a view taken substantially in the direction of the arrows indicated at 4-4 of FIGURE 3 and shows a portion of the door check and hold-open device in elevation as seen from the interior of the refrigerator.

Referring now more particularly to the drawings, a counter or chest-type refrigerator cabinet is indicated generally by the reference numeral 8. A door is pivotally mounted at 12 for opening and closing movement about a horizontal axis by spaced hinge brackets 14. These hinge brackets project from the refrigerator cabinet on opposite sides of the door. As shown in FIGURE 1, the door is movable between a closed position shown in full lines at A, an intermediate open position shown in dot-dash broken lines at B, and a fully opened position shown in broken lines at C. In its closed position, a sealing strip 15 carried by the door resiliently and sealingly engages the front face of the refrigerator cabinet adjacent the door opening therein.

A door check and hold-open mechanism constructed in accordance with the invention is mounted at each side of the cabinet and operably connected to the adjacent side of the door 10 in spaced relation to its pivotal mounting. Except for their opposite wall mounting requirements, these two mechanisms are structurally and 3,167,807 Patented Feb. 2, 1965 ice functionally the same. Hence, only the door check and hold-open mechanism mounted on the right-hand side of the refrigerator cabinet is herein shown and described for illustrative purposes. This mechanism comprises a folding linkage including a pair of links 16 and 18. These links are pivotally interconnected at 20 and extensible between the door and refrigerator cabinet at a location spaced from the hinge pivot 12. The outer end of the link 16 is pivotally connected at 20 to a bracket 24 suitably secured to the adjacent innerface of the door 10. The inner end of the link 18 forms a detented cam sector 26 and is drivingly secured at 28 to a pivot stud 30. The stud 30 is journaled in a stamped bracket member or plate 32. This plate is secured to the inner side wall 33 of the refrigerator body in mating relation with the recess 34 stamped therein. The bracket plate 32 and the recess 34 thus cooperate to define a spring housing chamber 35.

The end of the sector mounted pivot stud 30 extending within the spring chamber 35 is slotted to receive the inner end 36 of a spiral, clock-type torsional spring 38. The outer end of the spring 38 has a reverse bend 40 which engages an arm 42 extending laterally of a bell crank detent lever 43. The lever 43 is pivotally supported at 44 by the bracket 32 in spaced parallel relation to the cam sector and the axis of the pivot stud 30. A second depending arm 46 of the bell crank lever carries a roller 48. Rolling engagement between the roller 48 and the detented cam sector of the link 18 is normally maintained by the torsional biasing action of the spring 38. A pair of detent grooves or notches 50 and 52 formed in the sector are engageable by the roller to provide an intermediate hold-open position and a horizontal door supporting hold-open position.

As the door is swung open, the pivot stud 30 is rotated by door opening movement imparted to the sector link 18. This rotation of the pivot stud winds the spring 38 so that the bell crank lever 43 is increasingly biased in a clockwise direction, as viewed in FIGURE 1. This increased biasing action progressively urges the roller 48 into firmer engagement with the detented cam surface of the sector 26 thereby insuring proper door supporting and hold-open operation. The full opened detent groove 52 is preferably slightly deeper than the intermediate detent 50, as shown. The groove 52 thus normally serves to lock the door in its full opened horizontal position to support and maintain not only the door but also various items placed thereon prior to being placed in the refrigerator or subsequent to their removal therefrom. However, should the moment of the load acting on the opened door exceed a predetermined permissable amount, the extensible linkage rotates the detented sector 26 and carries the detent 52 out of locking engagement with the roller 48. This releases the door and permits it to drop to an inclined floor-engaging position causing the various items on the door to slide onto the adjacent floor. Such door overload releasing operation thus serves to protect the door from the destructive consequences of such overloading and prevents tipping of the partially loaded, free-standing refrigerator.

While the foregoing description has been limited to one illustrative embodiment of the door check and hold-open device of the invention, it will readily be apparent to those skilled in the art that various modifications may be made therein without departing from the spirit and scope as defined in the following claims.

What is claimed is:

1. In combination with a cabinet including a door pivotally hinged for downward swinging movement about a horizontal axis between a vertical closed position and a horizontal opened position, a hold open mechanism operable to normally maintain and support the door in a roller engageable with the detented outer-cam surface of saidsector, and torsional spring means interposed between and operably connected for biasing movement with both V the sector mountingpivot and a second arm on the bell crank lever wherebyv the bell crank journaled roller is'increasingly biased intofirmer door support- 1 ing and hold-open maintaining engagement with the detented' cam surface of the sector asutherdoor, is swung between its closed vertical position andits horizontal opened position.

2. Inthe combination defined in claim 1, said spring biased lever and detent engageable roller being operableto release said detented cam sector from its horizontal opened door supporting position when the moment of a load supported upon the door exceeds a predetermined safety factor.

3. In combination with a door mounted for pivotal swinging movement between closed and opened positions with reference'to a doorway defining structure, a holdopen mechanism comprising an extensible folding linkage means including apair of links pivotally connected at their distal ends to the: door and doorway defining structure in spaced parallel relation to the pivotal axis of the door, the distal end of the doorway supported link forming a detented cam sector,

a bell crank lever pivotally mounted in spaced relation to said sector and havingone arm journaling a roller engageable with the detented outer camsurface of,

said sector, I

and spring means torsionally connected between the sector mounting pivot and a second arm on the bell crank lever toprogressively bias the bell crank journaled roller into firmer door supporting and holdopen maintaining engagement with the detented cam ,4- surface of the sector as the door is swung between its closed and opened positions. 1

4. In combination with a door hinged and movable between a vertical closed and a horizontal opened position about a horizontal pivot axis, a door hold-open mechanism comprising a folding linkage pivotally connected and extensible between said door and the door supporting structure andv including a link having a detented cam surface thereon,

a lever pivotally supported in spaced relation to said cam surface and engageable therewith to provide intermediate dooropened positions,

and spring means torsiona'lly' interposed between said link and lever and operably connected to increasingly biassaid lever into firmer hold-open maintaining and door supportingengagement with the detented cam surface as the door is swung between its closed vertical position and its horizontal opened position.

5. In combination-with a hinged'door' and hold-open mechanism as set forth in claim 3 ,said spring biased'lever being operableto release said detented cam surface when the moment of a load, supported by said doorexceeds a predetermined limit.

6., In combination. with a door hinged and movable between closed and opened positions, a door hold-open mechanism comprising a folding linkage pivotally connected and extensible between said door and a door way defining supporting structure in spaced relation to the pivotal axis of the door and including a linkhaving detented cam surface thereon, a bell crank detent lever pivotally support in spaced relation. to said cam surface and engageable therewith to provide intermediate door opened positions,

and spring meansfoperably connectedto progressively bias said lever into firmer door supporting and holdopen maintaining engagement with the detented cam surface as the door is swung between its closed and opened positions.

References Cited in the file of this patent UNITED STATES PATENTS Putnam Jan.r1, 1952 

6. IN COMBINATION WITH A DOOR HINGED AND MOVABLE BETWEEN CLOSED AND OPENED POSITIONS, A DOOR HOLD-OPEN MECHANISM COMPRISING A FOLDING LINKAGE PIVOTALLY CONNECTED AND EXTENSIBLE BETWEEN SAID DOOR AND A DOOR WAY DEFINING SUPPORTING STRUCUTRE IN SPACED RELATION TO THE PIVOTAL AXIS OF THE DOOR AND INCLUDING A LINK HAVING DETENTED CAM SURFACE THEREON, 